I suggest that you do not attempt to find these locations or farmiliarize yourself with them during an actual match. Go to private match and set your time to unlimited, choose the proper map and practice this way. Or else you may find yourself getting frustrated and giving up on it all together. It never feels good when all you want to do is get to that one spot but for some reason you keep getting taken out before you get there. Now add the fact that you've never used this spot before. Make sense?

This one is a camping spot and is located in Vacant. Go to the bathroom area, enter the bathroom, now exit the bathroom through the hole in the wall (not the doorway). Take a right (not left through the door) when you take that righthand turn you'll be in a hallway. walk to the wall and turn right again. Now you will see crates blocking the way, you can jump over them, but don't. To make sure you are in the right place, turn left and you should be looking down a long hallway, while looking DOWN the long hallway, turn 90 degrees to the left, now you should be looking at the small inlet/nook that houses the hole in the wall to the bathroom. Turn another 90 degrees to the left and you should be looking at/over the crates that block the path. This is where you want to be. Remember DON'T jump over the crates, you want to be on the side with the hole to the bathroom, not the side with the door to the bathroom. Face down the long hallway again, now back up all the way till your back touches the crates. Crouch and work your way into the corner closest to the wall. You ultimately want to be in the corner between the opposite wall to the bathroom and the crates. I've gotten 15 and 16 kill streaks here. And done so on many occassions.So I know for me it's been a great spot.

Ok, this one is located in Bog and is very easy to find. However, I still beleive you should practice it/find it in a private match.

Ok, here is what you do. Find the buildings area. Now there is a building that contains a small hallway. You know the hallway that so many people seem to think is a great camping spot. But don't realize that a grenade changes that in about 3 seconds? My opinion, don't ever use this hallway for more than passing through.

Anyways, Go to this hallway and exit it through the door that leads outside. (Not the door that leads further into the building.)
Once outside there should be a wooden fence to your left. Now run all the way straight to the back wall, it's a nice little run, it should take you around 6-7 seconds to get there. Once here you will see the same fence to your left. Now turn and find the two barrels located just along the fence. They will be side by side to form an L shape with the fence. Now just between the barrels and the fence, there is a crack about 3 inches wide. Lie down and face this crack, now when you aim through the crack, your gun sight should be set on the door that you originally exited through. Now just wait and take out anyone who exits that door. I got an 18 kill streak here and a buddy on 360 got a 24 kill streak. This spot is good if you learn how to utilize it.

Ok, now this is a great sniping spot. It's located in overgrown. And to get to it, you have to first make your way to the dumpster on the backside of the stone wall. For those who are not farmiliar with this area, it's located in the back of the house with the attic, the house is located just near the barn, you'll find a ladder on the side of the house leading up to the attic (don't go there) Instead you want to walk along the wall away from the house, now at the end of the wall turn right, you should see a doorway to your right leading into a wooden shed type building, go through there and when you exit out you should be right near the dumpster. Jump up on the dumpster, then up onto the wall.

Once on the wall you can either go left twoards the house with the ladder and the attic, or you can go right, take the right instead. Jump onto the roof of the building you exited from earlier, now make your way to the roof of the covered bridge, jump up on there, make your way all the way to the other end of the covered bridge, careful to avoid any holes, it sucks to fall through and have to start all over again. Anyways, once at the other end of the bridge face left, walk to the corner and look down at the corner of the bridge you should see a wooden fence, if you don't see it below you, you are on the wrong side. Once here, drop down onto the fence and walk along the fence to the next building, jump up onto the roof and turn, you should see the barn in the distance, now you can lie down here and snipe anyone that comes along, and you used no glitches to get here. Nice, Remember when sniping, patience is everything.